PhD Qualifying Examination


"A Survey on Rate Control and Error Control Schemes
for Layered Video Multicast"

By Miss Xing Zheng


Abstract:

Transmission of video to a large group of users presents many
challenges, mainly due to the heterogeneity of users in terms of,
for example, their processing power and bandwidth. Scalable video
coding has recently become a promising approach to address the
heterogeneity issue by encoding the original video data into
multiple layers, each of which is transmitted to a unique
multicast group. In order to maximize the decoded video quality,
the receivers subscribe as many video layers as their bandwidth or
processing power can accommodate. This system is also known as
layered video multicast system.

To avoid network congestion, rate control schemes are deployed to
adapt the transmission rate of each layer to the dynamic network
conditions. Since packet loss is inevitable in the network, error
control is necessary to mitigate the effect of packet loss. We
review in this paper the proposed rate control and error control
schemes for the layered video multicast. Depending on where the
adding and dropping of layers is located, we classify the rate
control schemes into three categories: receiver-driven,
network-supported and hybrid schemes. In receiver-driven schemes,
receivers determine the number of layers they add or drop while
network-based schemes need support from routers to do such
operations. Regarding error control, we divide schemes into
ARQ-based, FEC-based and hybrid schemes according to error
recovery techniques adopted. For each scheme, we summarize the
main approaches and discuss the trade-offs. We conclude by
presenting some possible future directions in the field.


Date:     		Monday, 10 December 2001

Time:                   3:00p.m.-5:00p.m.

Venue:                  Room 2302
			Lifts 17-18

Committee Members:      Dr. Gary Chan (Supervisor)
                        Dr. Jogesh Muppala (Chairman)
			Dr. Brahim Bensaou
                        Dr. Mounir Hamdi


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